Flesh-eating screwworm detected 25 miles from U.S. border, USDA says
A recent discovery of a flesh-eating New World screwworm in Mexico, just 25 miles from the United States border, has raised concerns among U.S. officials. The parasitic fly was found in a 5-year-old goat in Mexico’s Coahuila state, which shares a border with southwestern Texas. This marks the closest encounter to U.S. soil since at least last September, according to federal data.
The U.S. Department of Agriculture has been tracking the spread of the New World screwworm in Mexico, with 32 cases identified in the Mexican state of Coahuila alone. Of these cases, 19 are currently active, posing a threat to livestock and other animals in the region. Overall, there have been 26,216 screwworm cases reported across Mexico, with over 2,700 still active.
To keep the public informed, the USDA provides updates twice a week on any new cases found within 400 miles of the U.S. in Mexico. Despite the proximity of the screwworm to the U.S. border, the department reassures that the pest is not currently present in the United States, and the risk to livestock, animals, and people remains very low.
In recent years, the New World screwworm has been detected closer to the U.S. than ever before. In April, it was found just 60 miles from the U.S. border in Mexico, prompting warnings from Texas officials. Outdoor enthusiasts have been advised to be cautious since late 2024, when the parasite was first detected in a cow in southern Mexico.
Last year, the first case of a New World screwworm infestation in a human was confirmed in the U.S. The Department of Health and Human Services announced the case in a traveler returning from El Salvador to Maryland. Fortunately, the individual recovered, and there was no evidence of transmission to others.
The New World screwworm is a parasitic fly that feeds on warm-blooded animals and humans. It lays its eggs in open wounds or orifices, where the larvae hatch and feed on living tissue. Typically found in South America and the Caribbean, the screwworm has been spreading northward in Central America and Mexico in recent years, posing a growing threat to livestock and humans alike.
As the USDA continues to monitor the situation and provide updates, it is crucial for residents near the border to remain vigilant and take precautions to prevent the spread of the New World screwworm. By staying informed and following guidelines from health officials, individuals can help mitigate the risks associated with this invasive parasite.
